Modeling and Optimization of Nonlinear Viscoelastic Behavior for Tissue-Engineered Blood Vessels.

Vascular tissue engineering technology uses tubular viscoelastic materials as intermediaries to transmit the mechanical stimuli required for the construction of vascular grafts. However, most existing studies rely on elastic models, which fail to capture the time-dependent nature of viscoelastic materials. Moreover, the long fabrication cycles, high costs, and complex parameter measurements in tissue engineering pose significant challenges to experimental approaches.

Double-Network Hydrogel Based on Methacrylated Chitosan/Hyaluronic Acid Coacervate for Enhanced Wet-Tissue Adhesion.

Developing robust wet tissue adhesives remains challenging due to interfacial water and irregular surfaces. While polyelectrolyte coacervates demonstrate promising hydrophobic/fluidic properties for wet adhesion, their low cohesion limits practical applications. Herein, a wet tissue bioadhesive based on coacervates formed from low- molecular-weight methacrylated chitosan (CSMA) and hyaluronic acid (HA) is reported.

Water-in-water emulsions stabilized by nano-chitin.

A water-in-water (W/W) emulsion consists of microdroplets was formed by the spontaneous liquid-liquid separation by mixing polyacrylic acid and chitosan oligosaccharide in water, and these microdropletes were stabilized by nano-chitin, formed water-in-water Pickering emulsions. By taking the advantage of interfacial adsorption of nano-chitin, the W/W emulsion droplets composed of polyacrylic acid/chitosan oligosaccharide (COS/PAA) polyelectrolyte coacervate were successfully stabilized. Research results indicated that composite microspheres were formed by the nano-chitin stabilized COS/PAA emulsion, and the size of these composite microspheres was related to the concentration and morphology of the nano-chitin.

A novel macroporous carboxymethyl chitosan/sodium alginate sponge dressing capable of rapid hemostasis and drug delivery.

Carboxymethyl chitosan (CMCS) and sodium alginate (SA), which are excellent polysaccharide-based hemostatic agents, are capable of forming polyelectrolyte complexes (PEC) through electrostatic interactions. However, CMCS/SA PEC sponges prepared by the conventional sol-gel process exhibited slow liquid absorption rate and poor mechanical properties post-swelling. In this work, a novel strategy involving freeze casting followed by acetic acid vapor treatment to induce electrostatic interactions was developed to fabricate novel PEC sponges with varying CMCS/SA mass ratios.

Green preparation of β-chitins from squid pens by using alkaline deep eutectic solvents.

Based on the assumption that protein could be removed by the combined mechanism of alkaline induced degradation and strong hydrogen bond interactions of deep eutectic solvents (DESs), β-chitins were successfully prepared from squid pens by using alkaline DESs formed by potassium carbonate and glycerol. The chemical structures of the DESs were investigated by H nuclear magnetic resonance (H NMR), attenuated total reflection Fourier transform infrared (ATR-FTIR) and molecular modeling, and the physicochemical property of the prepared β-chitins were characterized. The preparation yields was about 32 %, and DESs with KCO/glycerol of 1/10 could be reused for three times while maintaining high preparation yields (31 %-32 %) and degree of deacetylation of 66.

Deep Eutectic Solvents Based on L-Arginine and 2-Hydroxypropyl-β-Cyclodextrin for Drug Carrier and Penetration Enhancement.

By selecting L-arginine as the hydrogen bond acceptor (HBA) and 2-hydroxypropyl-β-cyclodextrin (2HPβCD) as the hydrogen bond donor (HBD), deep eutectic solvents (DESs) with various water content were prepared at the 4:1 mass ratio of L-arginine to 2HPβCD with 40 to 60% of water, and were studied for its application in transdermal drug delivery system (TDDS). The hydrogen bond networks and internal chemistry structures of the DESs were measured by attenuated total reflection Fourier transform infrared (ATR-FTIR) and H-nuclear magnetic resonance spectroscopy (H-NMR), which demonstrated the successful synthesis of DESs. The viscosity of DES was decreased from 10,324.

Liquid-crystalline behavior on dumbbell-shaped colloids and the observation of chiral blue phases.

Colloidal liquid crystals are an emerging class of soft materials that naturally combine the unique properties of both liquid crystal molecules and colloidal particles. Chiral liquid crystal blue phases are attractive for use in fast optical displays and electrooptical devices, but the construction of blue phases is limited to a few chiral building blocks and the formation of blue phases from achiral ones is often counterintuitive. Herein we demonstrate that achiral dumbbell-shaped colloids can assemble into a rich variety of characteristic liquid crystal phases, including nematic phases with lock structures, smectic phase, and particularly experimental observation of blue phase III with double-twisted chiral columns.

The Study of Deep Eutectic Solvent Based on Choline Chloride and L-(+)-Tartaric Acid Diethyl Ester for Transdermal Delivery System.

Deep eutectic solvents (DESs) based on choline chloride (C) and L-(+)-tartaric acid diethyl ester (L) were prepared and used in transdermal drug delivery system (TDDS). The internal chemistry structure including the formation and changes of hydrogen bonds of choline chloride and L-(+)-tartaric acid diethyl ester DES was characterized via attenuated total reflection Fourier transform infrared (ATR-FTIR) and H nuclear magnetic resonance (H NMR) spectroscopy. The stoichiometric ratio of choline chloride to L-(+)-tartaric acid diethyl ester as well as water content affected the viscosity, glass transition temperature (T), and drug solubility of the DES.

EEG signal classification of tinnitus based on SVM and sample entropy.

The prevalence of tinnitus is high and seriously affects the daily life of patients. As the pathogenesis of tinnitus is not yet clear, there is a lack of rapid and objective diagnostic modalities. In order to provide clinicians with an objective diagnostic approach, this paper combines time-frequency domain and non-linear power analysis to investigate the differences in the specificity of the EEG signal in tinnitus patients compared to healthy subjects.